1. Field of the Invention
This invention pertains to article handling, and more particularly to apparatus for separating and feeding stacked and/or nested containers or flat sheets of stiff materials such as cardboard container blanks.
2. Background Art
Modern machinery is capable of loading open top containers on a high speed basis with many kinds of articles. The articles and containers are fed in separate but synchronized parallel paths to a loading station, at which complements of the desired number of articles are deposited into the containers. Other industrial processes require feeding of sheets of flat material from a stack onto a conveyor, individually. Some containers are fed in flat form and folded after destacking into the shape of the final containers.
Types of open top containers have proliferated in recent years. Although the traditional paperboard carton is still in widespread use, other types of containers are becoming increasingly popular. For example, plastic trays of various sizes and shapes are widely used to hold beverage bottles and cans. The trays are generally characterized by having relatively low sides compared with their widths and lengths, i.e. the trays are quite shallow.
Plastic trays are fully formed when they reach the loading machine. Even with trays that are relatively shallow, it is highly desirable that the trays be nested within one another in a stack to conserve shipping and storage space. Accordingly, the ability to supply trays in nested stacks to a loading machine represents an advantage over non-nestable trays. On the other hand, before the trays can be filled, they must be separated from each other, removed from the stack and conveyed, one at a time to the machine loading station.
A need exists for machinery that separates stacked articles and feeds them individually onto a moving conveyor.